It has been proposed to shut-off the valves of some cylinders under certain operating conditions, as for example, at low load of the combustion engine or during low load requirements, thus rendering the corresponding cylinders ineffective in combustion engines having a plurality of cylinders. As a result of this temporary switching off and arresting, the cylinders do not operate during a load change whereby economical operation of the combustion engine may be possible.
A combustion engine of the foregoing type is disclosed in DE-OS No. 28 14 164, wherein the valves can be switched on or off as required. For this purpose, the plungers which are disposed between the cam shaft and the valves, are provided with parts which are rotatable towards each other and a gear and corresponding intermediate recesses which are disposed axially opposite of each other and which are either engaging with their gear teeth or with their corresponding recesses, whereby the valves can be either actuated or released. However, such a structure cannot be mounted in a plunger of normal common size, and, therefore, requires an increase of height of the plunger and consequently of the total combustion engine.